Pivoted bender and adjustable guide for metal tubing



Apnl 5, 1949. G. s. CLOUSE 2,466,331

, PIVO'I'ED BENDER AND ADJUSTABLE GUIDE FOR METAL TUBING Filed March 23, 1946 ll/A i ll .uvmvrogc Gepr ye 5. C/ouse Patented Apr. 5, 1949 PIVOTED BENDER AND ADJUSTABLE GUIDE FOR METAL TUBING George S. Clouse, Seattle, Wash.

Application March 23, 1946, Serial No. 656,751

Still further objects and advantages attaching to the invention will appear and be understood in the course of the following description and claim, the invention consisting in the novel construction and in the adaptation and combination of parts hereinafter described and claimed.

In the accompanying drawing:

Figure 1 is a top plan view of a machine constructed in accordance with the preferred embodiment of the present invention, and showing a length of tubing in process of being bent.

Fig. 2 is a fragmentary vertical sectional view on line 2-2 of Fig. 1.

Fig. 3 is a fragmentary vertical sectional view on line 3-3 of Fig. l, with the tubing being here indicated by dotted lines; and

Fig. 4 is a reduced-scale fragmentary top plan view of the machine, and distinguished from the disclosure of Fig. 1 in that the former-wheel portrayed in the latter has been removed and replaced by a. wheel of larger diameter.

According to the present invention there is provided a foundation block denoted by the numeral 5 and which is secured in any suitable manner, as by the bolts 6, to a bed or base (not shown), and this block may occupy a horizontal position or it may be disposed upright, as desired. Carried by the block and preferably made fast thereto is an upstanding stud-axle or journal pin 1, and removably mounted upon the axle is a former-wheel 8 which is provided in its periphery with a circumscriblng gIOOVe Ill. The groove is so shaped as to give a snug fit to a length of tubing laid thereagainst, and which is to say that the cross-sectional contour of the groove corresponds with the surfaee contour of the tubing which is to be bent, and the magnitude of the arc encompassed by the groove should closely approach 180.

Made rigid with and extending radially from the former-wheel is a lever-arm l2, and upon this arm is a jaw it placed to occupy a position radially removed from the floor of the groove a distance equal to or very slightly exceeding the diameter of the tubing to be bent. For preventing relative movement and consequent scufllng 1 Claim. (Cl. 153-40) between the clamped work and former wheel 8 said lever arm i2 is integrated therewith and projects flush, or approximately flush, with the lower face of said wheel. A block l4 carries the jaw, and there is provided a journal pin l5 which gives a wrist mounting to the block and which is in turn supported by the lever-arm and a complementing bracket or strut IS. The pin is placed parallel with the axle l on a line projected radial to the latter through the heel part of the block, an arrangement which, in conjunction with a milling of the face of the jaw, produces the effect of a wedge when drawing the lever-arm, in the presence of an introduced length of tubing, in the clockwise direction represented by arrow in each of Figs. 1 and 4. The milling of the jaw should be such as will give to the biting points which are thereby produced a sharpness similar to that of the teeth of a file.

Completing my bending machine is a roller H which serves as a keeper for the tubing which is being bent, being arranged to bear upon the trailing part of the tubing at a point rearwardly removed from the point at which contact is initiated between the tubing and the former-wheel. and supporting the roller for rotation about an axis parallelling that of the axle l is a journalpin Hi.

It becomes desirable, in adapting a single foundation block to variously sized former-wheels, that provision be made for shifting the journal-pin transversely in relation to the block, and in accomplishing this end I mount the pin upon a slide 20. Th slide has a free-running lit with a dove-tail slot 2| cut transversely into the face of the fountdation block, and for securing the slide member in the desired transversely adiusted position a cap screw 22 is threaded into such member and is caused to bear by its head upon a washer 23 which seats by its edges upon the face of the foundation block. Taking up on the cap screw perforce causes the slide member, through the lift force transmitted thereto. to exert a clamping action upon the side walls of the slot.

The present invention constitutes an especially advantageous device by which to bend the tubing employed in the construction of metal furniture. The procedure, in using the machine, is to apply a former-wheel of the desired diameter and, shifting the position of the roller as may be necessary, the lever-arm I2 is then located such as to describe a right angle by its intersection with a right-line tangent of the wheel projected along the underside of the roller. The tubing to be bent is brought under the roller and through the throat defined between the law I3 and the groove l0, projecting beyond the Jaw in a degree sufficient to obtain a purchase. The operator now dragzs th e lever-arm in a clockwise direction about the center of the former-wheel as an axis, and which causes-in the initial turning stage the file-teeth of the jaw to bite into the surface of the tubing to hold the advance end of the latter firmly to the Jaw. As the gripped end of the tubing progresses with the Jaw through stages of orbital generation, the following length of tubing is perforce held in its approach to the former-wheel to a. rectilineal path of travel by reason of the restraint imposed by the roller l1, and the inherent resistance of the tubing to the developing bend tends to draw the tubing inwardly toward the axis of orbital generation with the result that the tubing is held firmly against the floor of the groove and thus shapes itself exactly to the perimeter of the former-wheel. The tubing, bent to this shape, is found to be perfect in point of the cross-sectional form throughout the length, and which is to say that there is no tendency whatever for the tubing to become deformed as it is bent into the curving shapes of the various selectively employed former-wheels. To release the bent tubing from the former-wheel, it becomes necessary only that the lever-arm be backed off slightly, and the tubing can then be given counter-clockwise movement in relation to the former-wheel to withdraw the advance end of the tubing from the gripping throat. Where several bends are compounded on a single length of tubing, and the point of the grip lies intermediate the ends, the bent tubing can be readily manipulated to introduce the leading bend through and withdraw the same from the gripping throat or, in the alternative, the pin l5 can be removed from the block ll.

It is thought that the nature of the invention, and the manner of its use, will be clear from the foregoing. Departures from the embodiment which I have elected to illustrate will suggest themselves, and no limitations are to be implied from the foregoing description having express reference thereto, it being my intention that all forms of construction and variations in detail coming within the scope of the following claim are to be considered as comprehended by the invention.

WhatIclaim,is:

A machine for bending metal tubing comprising, in combination: a flat mounting base; a journal pin carried by and projecting above the base with its axis located normal to the latter; a former-wheel receiving a Journal mounting from the pin and having a lever-arm made an integrated part of the wheel and projecting radially therefrom flush or approximately flush with the lower face of the wheel, said wheel, between the root end of the lever-arm and its upper face, being provided in the perimeter with a circumscribing groove shaped, in point of its cross-sectional contour, to produce a snug seat for the tubing which is to be bent, said tubing being arranged and adapted to be fed in a tangential direction to the wheel: a journal pin carried by and projecting above the lever-arm to locate its axis parallel to the wheel-supporting journal pin; a strut bolted to the lever-arm and stabilizing the upper end of said arm-carried pin; means for attaching the leading end of the tubing to the lever-arm comprising a block member pivotally mounted on the pin between the lever-arm and the strut and providing a gripping Jaw offset laterally in the direction of the lever arms tube-bending movement beyond a radius of the wheel traversing the journal axis of the block member; and a rotatively mounted roller having in its perimeter a groove forming a seat for the tubing which is being fed to the wheel and carried by the mounting bwe to engage the stock at a point in advance of the latters contact with the wheel for imposing upon the tubing a force in opposition to the bending movement of the lever-arm.

GEORGE S. CLOUSE.

REFERENCES CITED The following references are of record in the tile of this patent:

UNITED STATES PATENTS Number Name Date 559,839 Brinkman May 12, 1896 601,403 'Rollins Mar. 29, 1898 1,401,394 Curtis Dec. 27, 1921 1,264,097 Lichtenberg Apr. 23, 1918 1,284,516 Whitecotton Nov. 12, 1918 1,601,405 Michalsen Sept. 28, 1926 1,644,555 Wagenbach Oct. 4, 1927 2,371,695 Lancaster Mar. 20, 1945 FOREIGN PATENTS Number Country Date 8,119 Great Britain Apr, 13, 1908 

